FIGURE S1. M06-2X/6-31+G(d,p) optimized structures of 1 and 2 in (a,d) gas phase, (b,e) dichloromethane, and (c,f) chlorobenzene dielectric. Atom color coding is as follows: cyan = C, red = O, blue = N, yellow = S; magenta = F, gray = H. Natural population atomic charge densities are shown as italics.

FIGURE S2. Negative-ion electrospray mass spectra (nESI-MS) recorded on the LC-MS. From the top – 1) unlabeled standard of 1; 2) iridium black, 1 day, D2; 3) iridium black, 2 days, D2; 4) catalyst 3b, 2.5 hours, 120°C, D2 5) iridium black, 3 days, T2; 6) catalyst 3b, 4 hours, T2

FIGURE S3. Deuterium distribution calculated from the intensities of isotopic peaks in the measured spectrum of [2H]1 (Figure 1, row 3) and compared to the computed one; MS-isotope profile of measured unlabeled standard of 1 was subtracted.

FIGURE S4. HRMS (TOF MS Cl+) of [3H]1 prepared via heterogenous catalysis by iridium black catalyst, CH2Cl2, D2, 2 days. ESI-HRMS analysis: found m/z = 483.0534 [M+H]-, calculated C17H12DO3NF9S requires m/z = 483.0535.

FIGURE S5. Deuterium distribution calculated from the intensities of isotopic peaks in the measured spectrum of [2H]1 (Figure 1, row 2), and compared to the computed one; MS-isotope profile of measured unlabeled standard of 1 was subtracted.

FIGURE S6. nESI-MS analysis of deuterated T0901317 (compound [2H]1, m/z = 595.0 [M+TFA-H]-). According to the intensities of peaks, MS (ESI-) showed 0.71 D were incorporated into target compound [2H]1 after 2.5h of homogenous catalysis by 3b in PhCl at 120°C under deuterium atmosphere.

FIGURE S7. Deuterium distribution calculated from the intensities of isotopic peaks in the measured spectrum of [2H]1 (Figure S6) and compared to the computed one; MS-isotope profile of measured unlabeled standard of 1 was subtracted.

FIGURE S8. HRMS analysis of deuterated T0901317 ([2H]1). ESI-HRMS analysis: found m/z 481.03792 [M-H]-, calculated C17H10DO3NF9S requires m/z 481.03842.

FIGURE S9. 1H NMR of deuterated T0901317 ([2H]1). The decreased integration at peaks shifting 7.69 ppm and 7.66-7.55 ppm indicated approximate 30% D and 20% D were incorporated into C-1’ and C-1, respectively.

FIGURE S10. nESI-MS analysis of [3H]T0901317 (m/z 596.0 [M+TFA-H]-). Determined by the intensities of isotopic peaks, [3H]T0901317 displayed a specific activity of 10.8 Ci/mmol.

FIGURE S11. Tritium distribution calculated from the intensities of isotopic peaks in the measured spectrum of [3H]1 (Figure S10) and compared to the computed one; MS-isotope profile of measured unlabeled standard of 1 was subtracted.

FIGURE S12. Radio-chromatographic analysis of isolated [3H]T0901317 indicated a radio-chemical purity of 99%.

FIGURE S13. 3H NMR of [3H]T0901317 showing non-selective incorporation of 3H into the target compound.

FIGURE S14. 3H-1H coupled NMR of [3H]T0901317 showing non-selective incorporation of 3H into the target compound.